Barrier is an open-source utility that simulates the functionality of a physical KCM switch through a network connection. Developed as a fork of the Synergy 1.9 codebase, it allows a single keyboard and mouse to control multiple computers by moving the cursor across the edges of each screen. The software operates on a server-client model where the machine with the physical input devices acts as the server and the secondary machines act as clients.

Comprehensive input sharing and security features

The software provides a unified workspace by sharing input across a local area network. Its primary features include cursor transitions between displays, a shared clipboard for texts and images, and customizable hotkeys for manual switching. To protect data during transit, Barrier includes optional SSL encryption for the connection between the server and clients. The configuration interface uses a grid-based layout to arrange the relative positions of different monitors. While the software is designed to be lightweight, users may need to adjust local firewall settings or grant specific operating system permissions to enable input and clipboard synchronization.

Seamless workflow integration

Barrier is frequently used in environments involving cross-platform development, content creation, and multi-system office setups. It eliminates the need for physical peripherals for each machine, reducing desk clutter and streamlining transitions between operating systems. Because the software relies on a local network connection, it maintains lower latency than cloud-based alternatives. However, users should note that certain modern display protocols are not natively supported, and the software’s file transfer capabilities are considered unreliable.

Functional utility for multi-device control

Barrier offers a robust solution for sharing peripherals across different machines without the cost of hardware switches. Its local-network approach prioritizes privacy and reduces reliance on external service providers, and uses local network communication with optional SSL encryption rather than cloud-based syncing.